Stock-Based Compensation - Activity Related to the Company's Incentive Equity Awards (Details) - $ / shares shares in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2019	Dec. 31, 2019
Employee Stock Option
Number of Options (in shares)
Options outstanding as of June 30, 2017 (in shares)		794
Options granted (in shares)		334
Options exercised (in shares)		(136)
Options canceled (in shares)		(103)
Options outstanding as of September 30, 2017 (in shares)	889	889
Weighted Average Exercise Price (in usd per share)
Options outstanding as of June 30, 2017 (usd per share)		$ 46.47
Options granted (usd per share)		47.13
Options exercised (usd per share)		36.42
Options canceled (usd per share)		58.75
Options outstanding as of September 30, 2017 (usd per share)	$ 46.85	$ 46.85
Time-Based Restricted Stock
Restricted Stock and Restricted Stock Units (in shares)
Non-vested restricted shares/units as of June 30, 2017 (in shares)		145
Grants in period (in shares)		0
Restricted shares/units vested (in shares)		(122)
Restricted shares/units forfeited (in shares)		(4)
Non-vested restricted shares/units as of September 30, 2017 (in shares)	19	19
Time-Based Restricted Stock Units
Restricted Stock and Restricted Stock Units (in shares)
Non-vested restricted shares/units as of June 30, 2017 (in shares)		408
Grants in period (in shares)		539
Restricted shares/units vested (in shares)		(113)
Restricted shares/units forfeited (in shares)		(41)
Non-vested restricted shares/units as of September 30, 2017 (in shares)	793	793
Performance-Based Restricted Stock Units
Restricted Stock and Restricted Stock Units (in shares)
Non-vested restricted shares/units as of June 30, 2017 (in shares)		414
Grants in period (in shares)	378	378
Restricted shares/units forfeited (in shares)		(36)
Non-vested restricted shares/units as of September 30, 2017 (in shares)	756	756

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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